The Content Of Trace Metals In Coals From Shanxi, Henan Province And Their Mode Of Occurrences

The content of trace metals in coal and their modes of occurrence are the determinant elements which influence their use in coal processing and the process of environmental effects. Studies on quantitative analysis and occurrence characteristics in coal can provide a theoretical basis on hazardous trace elements migration and enrichment rule with a view to finding effective controllable removal technology, which reduces environmental hazards of trace metals in coal. Therefore, there is vitally important theoretical and practical significance to study harmful content of trace metals in coal and the occurrence characteristics.In this paper, Using the airtight microwave digestion systems, uses the different acid, the power, the dissolved time to carry on the multiple microwave condition experiment, seeks dissolves the type effect best, the establishment microwave resolution processing coal sample optimized method. ICP-MS, atomic fluorescence spectrometer, XRD, sequential chemical extraction analysis and many other means of measurement are used to analyze As, Se, Pb, Cr, Cd, Hg and other trace element content and occurrence of trace metals status in coal in Shanxi and Henan, and application XRD to phase analysis inorganic mineral compositions in coal, in-depth analysis relationships between trace metals and mineral components, which reveals distribution properties of the trace metals in coal to provides theoretical basis on establishment geological and geochemical model of harmful trace metals gathering in coal.(1)From the coal sample resolution method, using the airtight microwave resolution method, uses the HNO3-H2O2 mix system to achieve dissolves the type effect best, optimized the experimental condition, provides the basis for the coal sample microwave resolution.(2)From the results of quantitative analysis, the average content of chromium, selenium and mercury in the samples in Shanxi are lower than that of Henan; while the average content of arsenic, cadmium are slightly higher than that of Henan. Compared with the national average, the average content of chromium, arsenic, cadmium are slightly higher; while the lead is far higher and selenium and mercury are slightly lower. The average content of chromium, arsenic, selenium, cadmium, lead and mercury in the samples in Henan are slightly higher than that of the national average.(3)From the results of qualitative analysis, in the samples there is mainly kaolinite, calcite and quartz, as well as some of illite, dolomite, and muscovite, pyrite, and anatase exit in individual samples.(4)From the results of occurrence analysis, the chromium, the arsenic, the selenium, the cadmium, the lead and the mercury have many kinds of modes of occurrence in the coal sample. Modes of occurrence of the most element focus on the clay mineral union condition, the organic synthesis condition and the sulfide union condition primarily, next for water-soluble condition and the exchange condition, the iron and manganese oxide condition and the carbonate condition.